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A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

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The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2).

Ronald Gelaro¹, Will McCarty¹, Max J Suárez²

¹Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD.

Journal of Climate

|February 6, 2020

Summary

NASA

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Area of Science:

Atmospheric Science
Climate Science
Earth System Science

Background:

The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) is NASA's latest atmospheric reanalysis dataset.
MERRA-2 builds upon its predecessor, MERRA, by incorporating new observation types and model updates.
It aims to provide a continuous climate analysis and serve as a foundation for future integrated Earth system analysis (IESA).

Purpose of the Study:

To provide an overview of the MERRA-2 system and its performance metrics.
To highlight advancements in MERRA-2, including aerosol assimilation and improved stratospheric and cryospheric representations.
To identify remaining deficiencies in the MERRA-2 dataset.

Main Methods:

Assimilation of various observation types, including aerosols.
Updates to the Goddard Earth Observing System (GEOS) model and analysis scheme.
Evaluation of performance metrics and comparison with MERRA.

Main Results:

MERRA-2 demonstrates improvements over MERRA, such as reduced spurious trends and biases in the water cycle.
Enhanced representation of the stratosphere, including ozone, and cryospheric processes.
Successful assimilation of aerosol observations, a key advancement for Earth system analysis.

Conclusions:

MERRA-2 represents a significant advancement in atmospheric reanalysis, crucial for climate research and IESA development.
The dataset offers improved accuracy and new capabilities, particularly with the inclusion of aerosol data.
Ongoing efforts will address identified deficiencies and further enhance the system for future climate studies.